Consuming web service with php

I’ve been searching around everywhere for info on consuming web services with php. I’ve found plenty of in depth tutorials for .net but not as much for php. This tutorial (http://www.kirupa.com/net/using_webService.htm) breaks it down really well, does anyone know of a similar one using php?

So far I’ve been reading everything I can find on wsdl and soap and have a decent concept of how it works, just don’t know how to set it up code wise. Most code thats been posted seems different from the rest. If anyone wants to take a stab at it, this is the web service I am trying to access below.

http://www.giftcards.com/api/api_soap.html#

how could I set this up in code and pass the proper variables to the activateCard method?

Any help or even a link to a tutorial similar to above would be greatly appreciated.

Thanks